JP2011-205875A discloses a bus bar unit in which insulating resin is interposed between three annular bus bars, namely a U phase bus bar, a V phase bus bar, and a W phase bus bar, and the bus bars are laminated in an axial direction of a stator.
JP2011-88406A discloses a method of forming a bus bar unit by supporting a plurality of bus bars using support pins of a die, and insert-molding the bus bars in this condition using insulating resin.